Any type inferred for circular reference due to import cycle

The inferred `Any` type is unexpected:

`t.py`:

```py
import t2
def f() -> None: pass
reveal_type(t2.f)  # Revealed type is 'Any'
```

`t2.py`:

```py
from t import f
```

A better option would be to reveal the correct type or generate an error if it's not possible.